In vitro and in silico protein corona formation evaluation of curcumin and capsaicin loaded-solid lipid nanoparticles.

Nanotechnology has been an important tool for the production of nanoparticles with controlled release of drugs for therapeutic applications. Here, we produced solid lipid nanoparticles (SLN) loaded with curcumin and capsaicin (NCC) following the overarching goals of green chemistry. Currently, besides evaluating the composition, and size of these, it is necessary to understand the interactions between nanoparticles and the biomolecules present in the biological medium. For this, assays were conducted in order to evaluate the potential formation of the protein 'corona', and to better understand the results obtained in vitro, we also performed an interaction study, in silico, between the NCC components and the main serum protein, albumin. In the first hour of contact between the NCC and the culture medium showed fluctuation in the diameter of the NCC. However, after 24 and 48 h of the incubation period, all NCC concentrations showed an increase in size, which can be attributed to plasma protein adsorption. Since, hard corona takes a few seconds, while the soft corona can be formed in minutes up to a few hours. On the other hand, best docking binding-poses of interaction for the formed docking complexes evaluated suggest interactions following the docking affinity like free energy FEB (Tween 80-bovine serum albumin) ≈ FEB (Span 80-bovine serum albumin) showing a pharmacodynamic pattern based in non-covalent hydrophobic interactions with the bovine serum albumin binding-site. Our in silico results clarify and reinforce our in vitro findings of corona formation, which represents the real interaction with cell membranes in vivo.

Preparation of mupirocin-loaded polymeric nanocapsules using essential oil of rosemary

Abstract The purpose of this study was to prepare and characterize mupirocin-loaded polymeric nanocapsules using two different oils and to develop and validate an analytical method for quantitative determination by high performance liquid chromatography. The mean size of the nanoparticles was 233.05 nm and 275.03 nm for nanocapsules with a rosemary oil like oily core and caprylic/capric triglyceride, respectively, and a good polydispersity index below 0.25 for both formulations. The nanocapsules showed good stability when stored at 40 ºC and room temperature for 30 days. The quantitative method was performed with a mobile phase consisting of ammonium ammonium acetate (0.05 M adjusted to pH 5.0 with acetic acid) and acetonitrile 60:40 (v/v); the flow rate was 0.8 mL/min, UV detection at 230 nm. The analytical method was linear in the range of 5.0-15.0 µg/mL, specific for both oils, accurate, precise (intermediate precision RSD = 1.68% and repeatability RSD = 0.81%) and robust under the evaluated conditions. Therefore, this method can be performed for quantification of mupirocin in polymeric nanocapsules containing both oils.

Inclusion complex of amiodarone hydrochloride with cyclodextrins: preparation, characterization and dissolution rate evaluation

ABSTRACT This study aimed to improve the water solubility of amiodarone hydrochloride (AMH) via inclusion complexes with β-cyclodextrin, methyl-β-cyclodextrin and 2-hydroxypropyl-β-cyclodextrin. Inclusion complexes were developed by physical mixture, coevaporation, spray-drying and freeze-drying. Solid state analysis was performed using X-ray powder diffraction, differential scanning calorimetry and scanning electronic microscopy. Thermodynamic studies demonstrate that the inclusion complexes of drug into different cyclodextrins were an exothermic process that occurred spontaneously. Water solubility and drug dissolution rates were significantly increased after the formation of inclusion complexes with the cyclodextrins evaluated in relation to the physical mixture and pure drug. The present study provides useful information for the potential application of complexation with amiodarone HCl. This may be a good strategy for the development of solid pharmaceutical dosage forms.

Amiodarone hydrochloride: enhancement of solubility and dissolution rate by solid dispersion technique

abstract Amiodarone HCl is an antiarrhythmic agent, which has low aqueous solubility and presents absorption problems. This study aimed to develop inclusion complexes containing hydrophilic carriers PEG 1500, 4000 and 6000 by fusion and kneading methods in order to evaluate the increase in solubility and dissolution rate of amiodarone HCl. The solid dispersion and physical mixtures were characterized by X-ray diffraction, FT-IR spectra, water solubility and dissolution profiles. Both methods and carriers increased the solubility of drug, however PEG 6000 enhanced the drug solubility in solid dispersion better than other carriers. Different media were evaluated for the solubility study, including distilled water, acid buffer pH 1.2, acetate buffer pH 4.5 and phosphate buffer pH 6.8 at 37 ºC. Based on the evaluation of the results obtained in the study phase solubility carriers PEG 4000 and PEG 6000 were selected for the preparation of the physical mixture and solid dispersion. All formulations were prepared at drug-carrier ratios of 1:1 to 1:10(w/w). The results of in vitro release studies indicated that the solid dispersion technique by fusion method in proportion of 1:10 (w/w) increased significantly the dissolution rate of the drug. X-ray diffraction studies showed reduced drug crystallinity in the solid dispersions. FT-IR demonstrated interactions between the drug and polymers.

resumo Cloridrato de amiodarona é um agente antiarrítmico que possui baixa solubilidade aquosa e apresenta problemas de absorção. Este estudo teve como objetivo desenvolver complexos de inclusão contendo carreadores hidrofílicos PEG 1500, 4000 e 6000 através dos métodos de fusão e amassamento para avaliar o aumento da solubilidade e taxa de dissolução do cloridrato de amiodarona. As dispersões sólidas e misturas físicas foram caracterizadas por difração de raios-X, espectroscopia no infravermelho com transformada de Fourier, solubilidade em água e perfis de dissolução. Ambos os métodos e carreadores aumentaram a solubilidade do fármaco, no entanto o PEG 6000 aumentou a solubilidade do fármaco na dispersão sólida mais que os outros carreadores. Diferentes meios foram avaliados para o estudo de solubilidade, incluindo água destilada, tampão ácido pH 1,2, tampão acetato pH 4,5 e tampão fosfato pH 6,8. Com base na avaliação dos resultados obtidos no estudo de solubilidade de fases, os carreadores PEG 4000 e PEG 6000 foram selecionados para a preparação das misturas físicas e dispersões sólidas. Todas as formulações foram preparadas nas razões fármaco-carreador de 1:1 a 1:10 (p/p). Os resultados de liberação in vitro que a técnica de dispersão sólida pelo método de fusão na proporção 1:10 (p/p) aumentou significativamente a taxa de dissolução do fármaco. Estudos de difração de raios-X mostraram redução da cristalinidade do fármaco na dispersão sólida. Análise por espectroscopia no infravermelho mostrou interações entre o fármaco e o carreador.

Validation of high performance liquid chromatography method for determination of meloxicam loaded PEGylated nanocapsules

abstract A method to ensure that an analytical method will produce reliable and interpretable information about the sample must first be validated, making sure that the results can be trusted and traced. In this study, we propose to validate an analytical high performance liquid chromatography (HPLC) method for the quantitation of meloxicam loaded PEGylated nanocapsules(M-PEGNC). We performed a validation study, evaluated parameters including specificity, linearity, quantification limit, detection limit, accuracy, precision and robustness. PEGylated nanocapsules were prepared by interfacial deposition of preformed polymer, and the particle size, polydispersity index, zeta potential, pH value and encapsulation efficiency were characterized. The proposed HPLC method provides selective, linear results in the range of 1.0-40.0 μg/mL; quantification and detection limits were 1.78 μg/mL and 0.59 μg/mL, respectively; relative standard deviation for repeatability was 1.35% and intermediate precision was 0.41% and 0.61% for analyst 1 and analyst 2, respectively; accuracy between 99.23 and 101.79%; robustness between 97.13 and 98.45% for the quantification of M-PEGNC. Mean particle diameters were 261 ± 13 nm and 249 ± 20 nm, polydispersity index was 0.15 ± 0.07 and 0.17 ± 0.06, pH values were 5.0 ± 0.2 and 5.2 ± 0.1, and zeta-potential values were -37.9 ± 3.2 mV e -31.8 ± 2.8 mV for M-PEGNC and placebo(B-PEGNC), respectively. In conclusion, the proposed analytical method is suitable for the quality control of M-PEGNC. Moreover, suspensions showed monomodal size distributions and low polydispersity index indicating high homogeneity of formulations with narrow size distributions, and appropriate pH and zeta potential. The extraction process was efficient for release of meloxicam from nanostructured systems.

resumo Para se assegurar que um método analítico produzirá informação confiável e interpretável sobre a amostra este deve ser inicialmente validado, tornando claro que os resultados podem ser confiados e rastreados. Neste estudo, propomos validar um método de cromatografia líquida de alta eficiência (CLAE) para a quantificação do meloxicam encapsulado em nanocápsulas PEGuiladas (M-PEGNC). Efetuamos a validação, avaliando parâmetros de especificidade, linearidade, limite de quantificação, limite de detecção, exatidão, precisão e robustez. As nanocápsulas PEGuiladas foram preparadas por deposição interfacial do polímero pré-formado e caracterizaram-se o tamanho da partícula, índice de polidispersão, potencial zeta, pH e eficiência de encapsulação. O método de CLAE proposto fornece resultados seletivos e lineares na faixa de 1,0-40,0 mg/mL; limites de quantificação e detecção de 1,78 mg/mL e 0,59 mg/mL, respectivamente; desvio padrão relativo para a repetibilidade de 1,35% e precisão intermediária de 0,41% e 0,61% para o analista 1 e analista 2, respectivamente; exatidão entre 99,23 e 101,79%; robustez entre 97,13 e 98,45% para a quantificação de M-PEGNC. Os diâmetros médios das partículas foram 261 ± 13 nm e 249 ± 20 nm; índice de polidispersão de 0,15 ± 0,07 e 0,17 ± 0,06, valores de pH de 5,0 ± 0,2 e 5,2 ± 0,1 e valores do potencial zeta de -37,9 ± 3,2 mV e -31,8 ± 2,8 mV para o M-PEGNC e o placebo(B-PEGNC), respectivamente. Concluindo, o método analítico proposto é adequado para o controle de qualidade do M-PEGNC. Além disso, suspensões mostraram distribuição de tamanho monomodal e baixo índice de polidispersão, indicando alta homogeneidade das formulações com distribuição estreita de tamanho, pH e potencial zeta apropriados. O processo de extração foi eficiente para a liberação do meloxicam dos sistemas nanoestruturados.

Development and validation of a dissolution method using HPLC for diclofenac potassium in oral suspension

The present study describes the development and validation of an in vitro dissolution method for evaluation to release diclofenac potassium in oral suspension. The dissolution test was developed and validated according to international guidelines. Parameters like linearity, specificity, precision and accuracy were evaluated, as well as the influence of rotation speed and surfactant concentration on the medium. After selecting the best conditions, the method was validated using apparatus 2 (paddle), 50-rpm rotation speed, 900 mL of water with 0.3% sodium lauryl sulfate (SLS) as dissolution medium at 37.0 ± 0.5°C. Samples were analyzed using the HPLC-UV (PDA) method. The results obtained were satisfactory for the parameters evaluated. The method developed may be useful in routine quality control for pharmaceutical industries that produce oral suspensions containing diclofenac potassium.

O presente estudo descreve o desenvolvimento e validação de um método de dissolução in vitro para avaliação da liberação de diclofenaco potássico suspensão oral. O teste de dissolução foi desenvolvido e validado de acordo com as diretrizes internacionais. Parâmetros como linearidade, especificidade, precisão e exatidão foram avaliados, bem como a influência da velocidade de rotação e a concentração de tensoativono meio. Depois de selecionar as melhores condições, o método foi validado usando o aparato 2 (pás), velocidade de rotação de 50 rpm, 900 mL de água com 0,3% de lauril sulfato de sódio (LSS) como meio de dissolução a 37,0 ± 0,5 ºC. As amostras foram analisadas pelo método de CLAE-UV (PDA). Os resultados obtidos foram satisfatórios para os parâmetros avaliados. O método desenvolvido pode ser útil na rotina de controle de qualidade para as indústrias farmacêuticas que produzem suspensões orais contendo diclofenaco potássico.

A simple method for the quantification of diclofenac potassium in oral suspension by high-performance liquid chromatography with UV-detection

A rapid, simple and low cost method was developed to determine diclofenac potassium (DP) in oral suspension, using a reverse-phase column (C8, 150 mm x 4.6 mm, 5 µm), mobile phase containing methanol/buffer phosphate (70:30 v/v, pH 2.5), at a flow rate of 1.0 mL/min, isocratic method, and ultraviolet detection at 275 nm. A linear response (r = 1.0000) was observed in the range of 10.0-50.0 µg/mL. Validation parameters such as linearity, specificity, precision, accuracy and robustness were evaluated. The method presented precision (repeatability: relative standard deviation = 1.21% and intermediate precision: between-analyst = 0.85%). The specificity of the assay was evaluated by exposure of diclofenac potassium under conditions of stress such as hydrolysis, photolysis, oxidation and high temperature. The method presented accuracy values between 98.28% and 101.95%. The results demonstrate the validity of the proposed method that allows determination of diclofenac potassium in oral suspension and may be used as an alternative method for routine analysis of this product in quality control.

Desenvolveu-se método simples, de baixo custo para determinar o diclofenaco potássico (DP) em suspensão oral, usando coluna de fase reversa (C8, 150 mm x 4,6 mm, 5 µm), fase móvel contendo metanol/tampão fosfato (70:30 v/v, pH 2,5), com fluxo de 1,0 mL/min, método isocrático e detecção no ultravioleta a 275 nm. Observou-se resposta linear (r = 1,0000) na faixa de 10,0-50,0 µg/mL. Avaliaram-se parâmetros de validação, como linearidade, especificidade, precisão, exatidão e robustez. O método apresentou precisão (repetibilidade: desvio padrão relativo = 1,21% e precisão intermediária: entre analista = 0,85%). A especificidade do ensaio foi avaliada pela exposição do diclofenaco potássico a condições de estresse, tais como hidrólise, fotólise, oxidação e alta temperatura. O método apresentou valores de exatidão entre 98,28% e 101,95%. Os resultados mostram a validade do método proposto, que permite a determinação de diclofenaco potássico em suspensão oral e pode ser utilizado como alternativa para análise de rotina desse produto no controle de qualidade.